- Phosphorus Ultra Low Range Colorimeter HI736 Hanna Checker - Marine Water
Monitoring phosphorus concentration in saltwater is important because it can cause corrosion if levels are too high. The Hanna HI736 Checker HC Handheld Colorimeter for Phosphorus ULR bridges the gap between simple chemical test kits and professional instrumentation. Accurate, affordable and easy to use. First, zero the instrument with your water sample. Next, add the reagents. Last, place the vial into the Hanna Phosphorus Checker, press the button and read the results. Done.
- Easier to use and more accurate than chemical test kits
- Large, easy to read digits Auto shut-off
- Dedicated to a single parameter
- Designed to work with HANNA's reagents
- Uses 10 mL glass cuvettes
- Small Size, Big Convenience
- Fits in the palm of your hand
- Range: 0 to 200 ppb
- Resolution: 1 ppb
- Accuracy: ±5 ppb ±5% of reading
- Light Source: LED @ 525 nm
- Light Detector: Silicon photocell
- Environment: 0 to 50°C (32 to 122°F); RH max 95% non-condensing
- Battery Type: (1) 1.5V AAA
- Auto-off: After 2 minutes of non-use and 10 seconds after reading
- Dimensions: 81.5 x 61 x 37.5 mm (3.2 x 2.4 x 1.5")
- Weight: 64 g (2.25 oz.)
- Method: Adaptation of Standard Method for Examination of Water and Wastewater, 20th edition, Ascorbic Acid method
Replacement Reagents - HI736-25 Phosphorus ULR Replacement Reagents
Which is better to test for, Phosphate or Phosphorus? Want to find out - Click Here
Pretty fun! By Jepoy on 6/27/2019Jepoy would recommend this product to a friendSo I got this to replace my other phosphate checker because I really wanted an accurate reading (number vs color) of my tank. Of course before buying this, I did some research on the pros and cons, and also watched the video on how to properly use it. The biggest worry I had was the 3:00 minute auto shut-off feature of the checker. I wasn't sure I'd be able to put the reagent, shake for 2 minutes and replace the cuvette back into the checker. Boy, that was always the fun part!!!! So what I do it get everything ready. I set a timer for 3 minutes. I get ready the reagent by cutting off two sides of the pack. I then create V trough at the open corner of the reagent pack. I seal the end of the trough by pressing it with my fingers and force all the reagent to the middle of the trough and set it aside. I fill the cuvette with 10 ml of tank water and wipe the outside with a lint free cloth. I make sure that I only touch the lid area of the glass. When placing the cuvette, I use the 10 ml text as a reference an face it towards me. I insert it inside the checker and press the button. Once it says add C2, I start my timer. I open the checker, get the cuvette, take off the lid and pour my reagents in. My timer will usually be at 2:30 mark when I'm ready to shake. I then shake for 2 mins leaving me 30 secs to wipe the cuvette and replace it back into the checker. I hold the button to start the 3:00 min timer of the checker. Piece of cake!!!
Anyways, I'm loving the checker. As stated, it is pretty accurate and better than color matching. I like how it spits out numbers. Of course it will say it in pbb and not ppm which is pretty easy to convert but I ask why didn't they just program the checker to spit the number out in ppm right of the bat? I'm guessing it has to do with accuracy. The checker can only display 3 digits so if you do the calculation yourself, you get more than 2 decimal places for the value thus accuracy.
The only issue I had with the checker is with regards to properly cleaning the cuvettes. I think they should have included a small bottle of their cleaning solution with the kit and also a lint free cloth. I was stuffing a piece of papertowel inside to clean it but find that it leaves some fiber inside the cuvette. I now rinse with RODI water first to get the saltwater out. Then I would place a couple of drops of alcohol and shake it around for 15 sec. I would then rinse it again with RODI water and air dry.
Works great if you plan !!!! By PD on 12/28/2018PD would recommend this product to a friendThis is the only hobby grade kit that will accurately check at low levels. My Red Sea kit can't detect what this one can. Also see the BRS video comparing phosphate tests.
Watch the Hanna video showing how the do the test: tap powder to bottom, fold, cut on dotted line to make a funnel, pour, then tear side of packet to get the rest out.
- You must have packet cut open and ready before starting the test.
- Time your checker with a stop watch with no actual test samples to learn how it works. When you put the first pure water sample in (no reagent yet) and press the button, it will analyze it and when done will say " Add C2 press". As soon as it says " Add C2 press" the annoying timeout clock starts to run. I timed mine. I have exactly 3 minutes and 15 seconds from when it says that until it times out. So set a countdown timer on your phone for 3:15 and start it as soon as " Add C2 press" shows up. Then remove the vial, pour in the packet, close the vial, and look at the timer. I'm usually down to 2 minutes and 30 seconds by then. So shake for two minutes per instructions, I'll then see I have 30 seconds left to wipe the vial, insert it in the proper orientation and press and hold the button. Yes it's a bit of a pain, but the upside is you can test phosphate really fast.
- Tip: always point the "10ml" on the vial forward so the first and second reading are through the same part of the glass vial. Hanna suggests this as the glass is apparently not perfectly uniform.
Awesome tester By David on 12/28/2018David would recommend this product to a friendI see many reviews saying the meter shuts itself off too quickly.
Once reagent is added there is a fairly short time frame to read results. This is for accuracy.
When running this test get everything ready, including opening the reagent envelope (use scissors and cut along the line), before turning the meter on.
If you follow directions it’s pretty easy and straight forward. And I find the meter gives consistently repeatable results.
Easy to use By Gina on 10/8/2018Gina would recommend this product to a friendHave read reviews on timer running out before dissolving powder. What I do is to use both vials provided. One for just saltwater and the other to mix powder BEFORE starting test. Once the powder is dissolved I start test. Turn on, calibrate (C1) with just water vial and switch to vial with dissolved powder (C2). No problem done in minutes. I've been using HI713 for over 3 years for tank and to double check my DI water just in case filters and resin needed to be changed. Have since upgraded to HI736.
Stupid test design errors By Wally on 8/23/2018Wally wouldn't recommend this product to a friendThis product has an obvious design errors - the time allowed to mix the reagent added, and the method of adding *all* reagent to the test vial. The product has an auto shut-off timer that is set to time recommended to mix the reagent, leaving *zero* seconds to remove the vial, add reagent and return the vial. An extra 30-45 seconds would be really useful, and I can't believe that the product managers and designers didn't see this ahead of time. Packaging of the reagents also makes it difficult to get all of the dose into the vial without spilling. Which is made even worse because you have to hurry to beat the shut-off timer. Why didn't the manufacturer look at these before releasing the product to the market?
Including more reagents in the base unit might be helpful. Also some sort of funnel would aid in getting the reagent into the small opening of the vial.
Hanna tech support forwarded a YouTube video suggesting one method of speeding up your mixing process and improving the adding of the reagent. Why isn't this part of the instructions provided?
Thoughtful product design and solutions to these issues offered with the product really could make this a good product. Then again maybe this is they way Hanna expects to increase their margin, through customers wasting reagent via uncompleted tests!
Some modification needed but overall a good device By Frank on 8/8/2018Frank would recommend this product to a friendThis device makes checking phosphorus much much easier. But after you add the reagent, only shake for 90 seconds as opposed to 2 minutes because the machine will automatically turn itself off in exactly 2 minutes. Not sure why the manufacturer haven’t thought about it.
Very frustrating device times out prior to completion of test By Luke on 6/25/2018Luke wouldn't recommend this product to a friendWell I burned through 4 of the six reagent packets (six really?) getting my speed testing regimen down with hard to handle packets of reagent. This is poor design; change the timeout programming so people don't have to hurry through the process.
Great Product By Esquare on 5/13/2018Esquare would recommend this product to a friendI have used the Hannah Low Range for a while and always got "0" so i tried this ULR and am now getting ".06" so for me it's working great!
Another great investment ! By Jason on 2/23/2018Jason would recommend this product to a friendYet another great investment along with the hanna ALK checker. Accurate, buy more regent kits though cause they don't give you a lot which I don't understand why. Remember the formula - reading x 3.066 / 1000 to get your number. I give it 4 stars cause they don't give you a lot of regent blaaaa
Works well, when you are careful By Matthew on 1/31/2018Matthew would recommend this product to a friendI too do the 2 cuvette trick with these, as getting it back into the checker in time to check it before it shuts off has been tricky for me so far. I wish that the checkers that have longer sit times such as this would not shut off as quickly, but otherwise, following the directions, making sure everything is clean, etc., provides accurate results.
Phosphorus and Alkalinity Checker (Hanna) By Jeffrey on 12/11/2017Jeffrey would recommend this product to a friendI have read the reviews of this unit and the criticisms. I understand what people say but I think when each test is planned correctly and prep work done before each test is begun, the issues were non existant and when the adjusted results were compared to a Red Sea Pro the results were accurate without the need to guess if the result was .01, .02 or .03 because the color was a shade lighter then the color on the wheel for .04. The consistency and repeatably were very good when the procedure for conducting the test was kept the same each time. It is important to not let the reacted sample sit for too long as the accuracy is greatly affected but for those shooting for ULNS its a must have! .
Meh By Ron on 12/11/2017Ron would recommend this product to a friendI'm rating this a 3 because..In the picture here you see a package of reagents for 25 test, but in reality you only get enough reagents for 6 tests...so you might as well order reagents when you buy this...Meh!!!
Why is there a timer? Is this the time it gives me to Dissolve the powder? Or does the sample have to be in the colorimeter the whole time?
Thanks for the question and have a great day!
Which checker should I use for a reeftank the hi713 or hi736 to check for phosphate?
We use the Hi713 in most cases as it is easier to use and read over the phosphorus which requires additional calculation to convert to phosphate.